1887

Abstract

The stability of actively growing heterokaryons made by fusing haploid and diploid plasmodia of has been investigated with the aid of genetic markers affecting plasmodial colour and amino acid requirements. All heterokaryons initially expressed the dominant alleles present in both component plasmodia, but after a few subcultures every heterokaryon synthesized from a haploid plus a diploid plasmodium changed to express the recessive alleles carried by the haploid component. In contrast, heterokaryons synthesized from combinations of haploid plasmodia remained stable throughout many subcultures. No evidence was found for the segregation of incompatibility alleles responsible for heterokaryon instability, although the possibility could not be excluded that a gene closely linked to was involved. A direct test of the effect of ploidy on heterokaryon stability was carried out, in which the use of isogenic haploid and diploid plasmodia allowed the effect of incompatibility genes to be eliminated. Again the phenotype of every haploid plus diploid heterokaryon changed to that of the haploid component, whereas haploid plus haploid heterokaryons remained stable. Variations in the relative sizes of the haploid and diploid plasmodia altered the speed, but not the direction, of the changes observed. Analysis of progeny indicated that the changes in phenotype were due to loss of diploid nuclei from the heterokaryons.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-131-5-1167
1985-05-01
2022-01-24
Loading full text...

Full text loading...

/deliver/fulltext/micro/131/5/mic-131-5-1167.html?itemId=/content/journal/micro/10.1099/00221287-131-5-1167&mimeType=html&fmt=ahah

References

  1. Adler P. N. 1975; Control of the differentiated state in Physarum polycephalum. PhD thesis Massachusetts Institute of Technology; USA:
    [Google Scholar]
  2. Adler P. N., Holt C. E. 1974; Genetic analysis in the Colonia strain of Physarum polycephalum: heterothallic strains that mate with and are partially isogenic to the Colonia strain. Genetics 78:1051–1062
    [Google Scholar]
  3. Adler P. N., Holt C. E. 1977; Mutations increasing asexual plasmodium formation in Physarum polycephalum. Genetics 87:401–420
    [Google Scholar]
  4. Anderson R. W. 1976; Analysis of the amoebalplasmodial transition in Physarum polycephalum. PhD thesis University of Leicester; UK:
    [Google Scholar]
  5. Anderson R. W. 1977; A plasmodial colour mutation in the Myxomycete Physarum polycephalum. Genetical Research 30:301–306
    [Google Scholar]
  6. Anderson R. W., Dee J. 1977; Isolation and analysis of amoebal–plasmodial transition mutants in the Myxomycete Physarum polycephalum. Genetical Research 29:21–34
    [Google Scholar]
  7. Anderson R. W., Truitt C. L. 1983; A new type of plasmodium formation in Physarum polycephalum. Genetical Research 42:285–296
    [Google Scholar]
  8. Anderson R. W., Youngman P. J. 1985; Complementation of npf mutations in diploid amoebae of Physarum polycephalum: the basis for a general method of complementation analysis at the amoebal stage. Genetical Research in the Press;
    [Google Scholar]
  9. Border D. J., Carlile M. J. 1974; Somatic incompatibility following plasmodial fusion between strains of the Myxomycete Physarum polycephalum: the effect on their nuclei. Journal of General Microbiology 85:211–219
    [Google Scholar]
  10. Burland T. G., Chainey A. M., Dee J., Foxon J. L. 1981; Analysis of development and growth in a mutant of Physarum polycephalum with defective cytokinesis. Developmental Biology 85:26–38
    [Google Scholar]
  11. Carlile M. J. 1972; The lethal interaction following plasmodial fusion between two strains of the Myxomycete Physarum polycephalum. Journal of General Microbiology 71:581–590
    [Google Scholar]
  12. Carlile M. J. 1976; The genetic basis of the incompatibility reaction following plasmodial fusion between different strains of the Myxomycete Physarum polycephalum. Journal of General Microbiology 93:371–376
    [Google Scholar]
  13. Carlile M. J., Dee J. 1967; Plasmodial fusion and lethal interaction between strains in a Myxomycete. Nature London: 215832–834
    [Google Scholar]
  14. Collins O. R. 1972; Plasmodial fusion in Physarum polycephalum: genetic analysis of a Turtox strain. Mycologia 64:1130–1137
    [Google Scholar]
  15. Collins O. R., Betterley D. A. 1982; Didymium iridis in past and future research. Cell Biology of Physarum and Didymium I25–57 Aldrich H. C., Daniel J. W. New York: Academic Press;
    [Google Scholar]
  16. Collins O. R., Haskins E. F. 1972; Genetics of somatic fusion in Physarum polycephalum: the PpII strain. Genetics 71:63–71
    [Google Scholar]
  17. Cooke D. J. 1974; Studies on the Colonia isolate of Physarum polycephalum. PhD thesis University of Leicester; UK:
    [Google Scholar]
  18. Cooke D. J., Dee J. 1974; Plasmodium formation without change in nuclear DNA content in Physarum polycephalum. Genetical Research 23:307–317
    [Google Scholar]
  19. Cooke D. J., Dee J. 1975; Methods for the isolation and analysis of plasmodial mutants in Physarum polycephalum. Genetical Research 24:175–187
    [Google Scholar]
  20. Dee J. 1966; Multiple alleles and other factors affecting plasmodium formation in the true slime mold Physarum polycephalum Schw. Journal of Protozoology 13:610–616
    [Google Scholar]
  21. Dee J. 1978; A gene unlinked to mating-type affecting crossing between strains of Physarum polycephalum. Genetical Research 31:85–92
    [Google Scholar]
  22. Dee J. 1982; Genetics of Physarum polycephalum. Cell Biology of Physarum and Didymium I211–251 Aldrich H. C., Daniel J. W. New York: Academic Press;
    [Google Scholar]
  23. Dee J., Poulter R. T. M. 1970; A gene conferring actidione resistance and abnormal morphology on Physarum polycephalum plasmodia. Genetical Research 15:35–41
    [Google Scholar]
  24. Dee J., Wheals A. E., Holt C. E. 1973; Inheritance of plasmodial valine requirement in Physarum polycephalum. Genetical Research 21:87–101
    [Google Scholar]
  25. Gingold E. C., Grant W. D., Wheals A. E., Wren M. 1976; Temperature-sensitive mutants of the slime mould Physarum polycephalum. II. Mutants of the plasmodial phase. Molecular and General Genetics 149:115–119
    [Google Scholar]
  26. Gorman J. A., Dove W. F., Shaibe E. 1979; Mutations affecting the initiation of plasmodial development in Physarum polycephalum. Developmental Genetics 1:47–60
    [Google Scholar]
  27. Haugli F. B. 1971; Mutagenesis, selection and genetic analysis in Physarum polycephalum. PhD thesis University of Wisconsin; USA:
    [Google Scholar]
  28. Kubbies M., Pierron G. 1983; Mitotic cell cycle control in Physarum. Unprecedented insights via flow-cytometry. Experimental Cell Research 149:57–67
    [Google Scholar]
  29. Laffler T. G., Dove W. F. 1977; Viability of Physarum polycephalum spores and ploidy of plasmodial nuclei. Journal of Bacteriology 131:473–476
    [Google Scholar]
  30. Lane E. B., Carlile M. J. 1979; Post-fusion somatic incompatibility in plasmodia of Physarum polycephalum. Journal of Cell Science 35:339–354
    [Google Scholar]
  31. Mc Cullough C. H. R., Cooke D. J., Foxon J. L., Sudbery P. E., Grant W. D. 1973; Nuclear DNA content and senescence in Physarum polycephalum. Nature New Biology 245:263–265
    [Google Scholar]
  32. Mittermayer C, Braun R., Rusch H. P. 1965; The effect of actinomycin D on the timing of mitosis in Physarum polycephalum. Experimental Cell Research 38:33–41
    [Google Scholar]
  33. Mohberg J. 1977; Nuclear DNA content and chromosome numbers throughout the life cycle of the Colonia strain of the Myxomycete Physarum polycephalum. Journal of Cell Science 24:95–108
    [Google Scholar]
  34. Mohberg J. 1982a; Ploidy throughout the life cycle in Physarum polycephalum. Cell Biology of Physarum and Didymium I253–272 Aldrich H. C., Daniel J. W. New York: Academic Press;
    [Google Scholar]
  35. Mohberg J. 1982b; Composition of a plasmodium. Cell Biology of Physarum and Didymium II343 Aldrich H. C., Daniel J. W. New York: Academic Press;
    [Google Scholar]
  36. Mohberg J., Rusch H. P. 1971; Isolation and DNA content of nuclei of Physarum polycephalum. Experimental Cell Research 66:305–316
    [Google Scholar]
  37. Mohberg J., Babcock K. L., Haugli F. B., Rusch H. P. 1973; Nuclear DNA content and chromosome numbers in the Myxomycete Physarum polycephalum. Developmental Biology 34:228–245
    [Google Scholar]
  38. Mulleavy P., Collins O. R. 1981; CIPC-induced and spontaneously produced diploid myxamoebae in a Myxomycete, Didymium iridis: a study of mating-type heterozygotes. Mycologia 73:62–77
    [Google Scholar]
  39. Poulter R. T. M. 1969; Senescence in the Myxomycete Physarum polycephalum. PhD thesis University of Leicester; UK:
    [Google Scholar]
  40. Poulter R. T. M., Dee J. 1968; Segregation of factors controlling fusion between plasmodia of the true slime mould Physarum polycephalum. Genetical Research 12:71–79
    [Google Scholar]
  41. Tyson J. 1982; Periodic phenomena in Physarum. Cell Biology of Physarum and Didymium I61–110 Aldrich H. C., Daniel J. W. New York: Academic Press;
    [Google Scholar]
  42. Tyson J., Garcia-Herdugo G., Sachsenmaier W. 1979; Control of nuclear division in Physarum polycephalum. Comparison of cycloheximide pulse treatment, UV irradiation, and heat shock. Experimental Cell Research 119:87–98
    [Google Scholar]
  43. Wheals A. E. 1970; A homothallic strain of the Myxomycete Physarum polycephalum. Genetics 66:623–633
    [Google Scholar]
  44. Youngman P. J., Pallotta D. J., Hosler B., Struhl G., Holt C. E. 1979; A new mating compatibility locus in Physarum polycephalum. Genetics 91:683–693
    [Google Scholar]
  45. Youngman P. J., Anderson R. W., Holt C. E. 1981; Two multiallelic mating compatibility loci separately regulate zygote formation and zygote differentiation in the Myxomycete Physarum polycephalum. Genetics 97:513–530
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-131-5-1167
Loading
/content/journal/micro/10.1099/00221287-131-5-1167
Loading

Data & Media loading...

Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error